Electric switch



7 March 29, 1932. CARLSON 1,851,157

ELECTRIC SWITCH Filed March 29, 1929 INVENTOR.

:Ztzdmbk B Y A TTORNEYS.

' r Patented" Mar. 1932 is FFrs v FREDERICK GALSQNQ; on NEW BRITAIN, conNno'rIcU'r, lemma TO nANnnns, FEAR-Y8: CLARK; ongnnw'nnlrnrm; CONNECTICUT, Aconrona'r on or. comqnc'rr- Q and moreparticularly to that typeknown as 1 member or contactorhas a shifting or Vary our 1 ELECTRIC swrrcn i 1 Application filed March 29, 1929. Serial No; 350,862.

This invention relates to electricswitches snap" switches. 2

1 These; switches arecomnionly 'use dilwith. Z5 relatively.large'current, for example, 1n constoves and-other trolling circuitsfortoasters, householdappliances.

' It is'an object, oithe-ini ention tovprovide:

a snap switch in which the movable switch ingpivot, resulting in speedy, accelerated movementinto and out of circuit closing p0 sition with consequent reductlonof arcs and longer life of the switch in service.

for imparting an eccentricmovernent; to the contactor to ease the tens10n and strains, on the spring.

I -With these; general objects in view,1 the',in-- 'vention consists in the features, comb1nat1ons,.

Figure '1 a plan We nection Withtheaccompanying-drawings and; p p p connected electricallythrough said arms and, a bridge. The COIlt1CtOI,aS shown, is of uni- .in; accordance with the'invention; I

1 Figure 2 is a similar View of a modified Figure t is a" detail plan and sectional yiew: ofjpart of the actuator of the switch showninFigureQ;

V Figure {5 is a perspective View of th con-1 tactor ofthe-switch; I i igures'G, 7,;"and 8 are-diagrammat cviews (enlarged) showing, the, contactorf in, diner; ent position occupied'dur'ing movement;

Theconstruction illustrated as an example;

' comprises 'a housing IOfof insulating mate-" rial an d s-formed in Qtwoparts ,for assembly 1 in-pas s, Such hou's'ings are; well known' in" I the art; Enclosed "within j the housing fare two socket conn'ector's 11 andl2,"lone ofiwhich', 11, is {connected directly to ailead-fin ;w;iiiie through: 'metallic I conducting strip! 13,; theether 2 o, h ot dfinwifi q ghe he It :is further object to produce a ,plvoty -parts broken y and i n of a switch construct-ed switch which tlOIl; l

the housing..- The, switchflolock is formed ofinsulatingmaterial, such as porcelain. A

incorporates the present-invem In the illustrated embodiment, a switch block 14: is enclosed'with'inthe two parts of V contact plate 15 is.attachedlon;oneside-of the block'and has 'aflixed thercto the socket con- A nector, 12,.which isin electrical engagement.

with the plate. Onthe oppositeside of theblock,.another contact'plate .(notshown), is secured, 'Tothe second-contact plate, the lead-in wire forv socket 152 :is connectedthrough conducting strip, l6. v There is provide cl 'a" co'ntactor? or makeing and disconnecting the contact plates; AS

nected by a bridge, 18,,whi'ch straddles the" lolock in aslot 19 thereof. 1 vVVhe'n thewcont acctor is in circuit-closing position, the armsl 'ix engage the contact platesand said plates arel tary sheet-metalconstruction. l

1 and-break element for electrically connect-i reducethe p where shown as an example, the contactor in clujdes a pair'ofcurved contact arn1s,-17,con

The invention includes means for-so 1nount+ ing the *"contactor as to, give 'it'a shifting or;

- variableflpivot during its movements into and out ofcircuit closing positionyln the em- I bodiment here-illustrated, the-switch block. isformed with. recesses in the opposite sides 4 thereof and for thencconmiodation\oflegs. l

20 which ,eXtend'fErOm the contact 'armslT of the contactor. The legs areiadapted-to oscillate or swingbackfand forthfin the re .7

cesses andcarry thecontactgarms.intoand outof engagement wltlrtlie contactlplates.

Although capable 1 or various constructions,

oblique angularly clispos'ed side Walls 21, de

substantially-j semi-circular fiiorination and walls; flhe curyedwall .of: the notch ineet's 1the angnla1 side wallsj at sharp icorners,y23,

which, in fact," act'as, shoulders orrpitots,

ropens -o intogthe angularispacebetween the s pr entlyd s ibe I Ihwafl of the; notch ashereinshown,eachrecess isdesigned with .9011

and portions of the angularly disposed walls may be lined with thin sheet metal, 24, to provide a metallic bearing surface and eliminate wear on the material of the block.

The ends of the legs extend into the angular spaces of the recesses through the open ends thereof and have free hearings in the notches. The legs terminate in curved ends for sliding frrely over the curved surfaces of the notches. Although subject to modification in design, each of the leg ends is formed with relatively sharply curved bearing portions, one, 25, at the bottom end and one 26, 27 at each side, the sharply curved portions being connected by relatively slightly curved portions. There is thus produced a substantially pear-shaped end on each leg. As the legs oscillate, one or the other of the bearing portions ride on the curved surfaces of the notches. On one side of each leg, there is a straight edge, 28, which abuts and contacts with a side wall, 21, in one extreme position of the leg. Another straight edge, 29, is provided on the opposite side of each leg for engagement with the other side wall, 21, in the other extreme position of the leg. The extreme positions of the legs are thus defined and limited by the angularly disposed side walls of the recesses.

Means are-provided for actuating the contactor to move it into and out'of circuit closing position. In the example herein disclosed, the actuating means include a coil spring, 30, which extends throu h the switch block and has one end attache(v centrally to the bridge, 18. The other end of the spring is connected to a movable actuating member. The actuating member is exemplified as a slide, 31, which is arranged transversely in the block opposite the contactor and is adapted for rectilinear movement in a slot of the block. The slide and contactor are pulled toward each other by the spring with the result that the'slide is firmly held in its slot and theleg ends of the contactor forcedinto the curved notches. The spring end is at tached to the slide, substantially below the notches, and, to this end, a hook, lug or other catch, 33, may be provided on the shell for the engagement of the spring end. The op- 6 ends of the slide project'through and the housing and are equipped with buttons; 34, 35.

The switch is operated by moving the slide back and forth by pressure applied to buttons, 34, 35. The movement oft-he slide carries the spring and secured thereto with it, changes the axis of the spring, and, consequently the line off orce or pull of thespring. With the contactorin open circuit position shown in l, the line of pull of the spring is to thcright oi the pivot of the contactor and the contactor is held firmly against the righthand-wall, 21. When the slide is moved to theleft by pressure applied to button 34, the

spring end attached to it is carried with it, the line of pull of the spring is changed, and travels past the pivot of the contactor. The spring then exerts its pull on the left hand side of the pivot and causes the contactor to snap over until limited by left-bend wall, 21. The circuit is now closed by the contact arms, 17, engaging the contact plates on the switch block and completing the circuit between the plates through the contactor. The circuit is again broken by applying pressure to the other button, 35, and moving the slide to the right, thereby causing the line of force of the spring to move to the right of the pivot of the contactor and the contactor to snap back into its open circuit position against right-hand wall, 21.

The pivot of the contactor shifts during movement. In the circuit closing position, as shown by. Figure 6, the edges, 29, of the legs of the contactor engage the left-hand walls, 21, of the recesses and the pear-shaped ends bear against the right side of the notches. Upon movement of the slide to the right, the contactor first pivots around the left corners, 23, and the pear-shaped ends-slide down the notches, 22. When the legs are lifted off said corners (Figure 7), the pivot is changed to the pear-shaped ends, and points of contact of said ehds,the bottom and left said curved portions, 25, and 26,with the walls of the notches. These points of contact slide smoothly on the walls of the notches. The result is a speedy movement'of thc obntactor occurring just as the circuit is broken as well as a rolling or eccentric movement which persists until the edges, 28, of the contactor strike the righthand orners, 23, and the contactor rocksinto' the open circuit position. (Figure 9.) The contactor has essentially an initial pivotal movement on corners, 23, and a subsequent rolling or eccentric movement as the'pear-shaped ends act as the pivots, on the curved walls of the notches. The reverse of these movementsoecur'as-the contwctor moves to circuit-closing position.

The speedy movement of the cohtactor' just asit ma es or breaks the circuit is very efict'rve in reducing and breaking arcs that tend to occur. The eccentric movement of the contactor cases the torsion and reducestbe strain on the spring, prolonging the life of the spring and allowing the use of a stifier spring than in the ordinary snap switch. The shifting variable pivot has the further advantage in that the contactor is thrown on or oil' with a shorter movement of the slide and with less effort.

'In the modification shown in Figures'2, 3, and 4, the switch is-positioned in an inslilat ing casin 40, and acts to connect or disconneat con actors, 41'. Tfiqactaatorembodis a de, 42, havinga lu 33, for engagin" th of the spring. 12' slide is posi one'd within the casing and'ismanipulated from m ifs fin

outside thecasing. To this end',' -a sli de button, 44, may be located on the exterior of the casing candprovided with a boss, 45, extend-n 1 mg through a slot, 46,into the interior. Provisionis made for detachably securing the 1 boss to slide, 42. For this purpose, a screw, 47, having a'thinelongatedhead, 48, maybe threaded into the boss, 45: The head is passed through a narrow elongatedslot,49,in slide 42, and then given a turn,cas in Figure 4,,to prevent its withdrawal. This provides a i firm, yet detachable connectionofbutton, l4,

to slide, 42. p I a What is, claimed is:

terminating in a substantially pear-shaped free'end extending into said notch, said leg havingstraight edges for abutment with the sidewalls in extreme positions of the con-' 1 a tac'tor, an actuator, resilient means associated with the contactor and operatedby the actu- 1 ator to impart snap movements to thecontactor, and a contact engaged ordisfengaged by the contactor. I

having a curved, substantially semi-circular notch terminating in'sharp corners, a-con-.

tactor including a leghaving an end seatin 1 swingingfsnap movements, the leg pivoting on the sharp cornersduring portions of the in said notch, means to maintainrthe legen in, said notch and to impart to the cont-actor movements and rolling on the-curvedsurface of the notch'during other portions of the movements and a contact engaged or disengaged by the contactor.

In testimony whereof I'havehereunto set my hand. 7

I FREDERICK ELCARLSONN its 2. An electric switch comprising-a member 

